Jul 04, 2012

(Phys.org) -- The worlds oceans are increasingly pumping tropical warm water towards the poles with important consequences for life on Earth, according to a new study.

The tropical regions of the Indian, Pacific and Atlantic Oceans appear to be acting like a heart, accumulating heat and then pulsing it in bursts across the planet.

When the warm water reaches the continental shelves, it peels off in northerly and southerly directions, travelling along the shelf-line towards the poles. According to scientists at Plymouth Universitys Marine Institute and the National Centre for Scientific Research (CNRS), many of the pulses coincide with El Niño events  and their heat content is increasing in intensity.

The lead author of the report, Professor Philip Reid, of the Sir Alister Hardy Foundation for Ocean Science (SAHFOS) and the Marine Institute, said the global mechanism provided an explanation for the timing and connection of a wide-range of observed hydrographic, ecosystem and cryospheric (frozen ice/snow) events.

He said: We have described for the first time a globally synchronous pattern of pulsed, short-term (one year) emanations of warm temperatures that pass along continental shelves, from tropical seas to the poles.

Warm tropical waters appear to be acting like a heart, accumulating heat and energy, and then pumping it in bursts that progressively move toward the poles, a process that seems to be accelerating.

Reid and research partner Dr Gregory Beaugrand mapped and statistically analysed average temperatures for every two-degree square of latitude and longitude, from 1960 until 2008 for the whole global ocean, with a finer single degree resolution along continental shelves. They found a remarkable degree of symmetry, both north and south of the equator, and very clear spikes in the temperature followed by a period of cooling.

Co-author of the report Dr Beaugrand said: "We found sudden increases in temperatures in 1976, 1987, 1998, and throughout the first decade of the new millennium that coincided with well-documented ecosystem changes."

In the late 1980s for example, the change occurred at the same time as the collapse of the cod fishery off Eastern Canada; while in 1998, there was evidence of a transarctic migration of species from the Pacific to the Atlantic that was enabled by melting sea-ice.

Dr Beaugrand said: When you compare the timing of these warm sea surface temperature anomalies with the reductions of polar sea-ice in the Arctic and to the west of the Western Antarctic Peninsula, and the melting of ice shelves in Antarctica and Greenland, they coincide to a strong degree.

In conversation with Prof. Reid, Dr Doug Martinson, of Lamont-Doherty Earth Observatory, USA, described the contrast between the temperature at the bottom of the ice shelves of Western Antarctica and the warm water that is now penetrating from the adjacent shelf edge as comparable to a dragon blowing flames at the base of the ice.

Professor Reid concluded: The discovery of this new mechanism by which heat from the tropics is being moved in this pulsating manner has major and wide-ranging implications for mankind, influencing energy consumption, weather, extreme events, the cryosphere, forest fires, heat waves, droughts and ecosystems.

If this pattern continues, global temperatures may continue to rise in sudden jumps  and the evidence suggests that the rate of rise is accelerating.

The report  Global synchrony of an accelerating rise in sea surface temperature  is published in the Journal of the Marine Biological Association today.

Related Stories

An analysis of prehistoric "Heinrich events" that happened many thousands of years ago, creating mass discharges of icebergs into the North Atlantic Ocean, make it clear that very small amounts of subsurface warming of water ...

Accelerated melting of two fast-moving outlet glaciers that drain Antarctic ice into the Amundsen Sea Embayment is likely the result, in part, of an increase in sea-surface temperatures in the tropical Pacific Ocean, according ...

Reporting this week in the journal Nature, an international team of scientists led by British Antarctic Survey (BAS) has established that warm ocean currents are the dominant cause of recent ice loss from A ...

The Greenland and Antarctica ice sheets are melting, but the amounts that will melt and the time it will take are still unknown, according to Richard Alley, Evan Pugh professor of geosciences, Penn State.

Thirty-eight million years ago, tropical jungles thrived in what are now the cornfields of the American Midwest and furry marsupials wandered temperate forests in what is now the frozen Antarctic. The temperature differences ...

Recommended for you

In their open-access paper for Geology, Kimberly Genareau and colleagues propose, for the first time, a mechanism for the generation of glass spherules in geologic deposits through the occurrence of volcan ...

An analysis of buildings tagged red and yellow by structural engineers after the August 2014 earthquake in Napa links pre-1950 buildings and the underlying sedimentary basin to the greatest shaking damage, ...

As everyone who lives in the San Francisco Bay Area knows, the Earth moves under our feet. But what about the stresses that cause earthquakes? How much is known about them? Until now, our understanding of ...

(Phys.org)—A trio of researchers with the Indian Institute of Science has found, via computer simulation, that deforestation in one part of the world can impact rainfall patterns in another. In their paper ...

It's no surprise that Arctic sea ice is thinning. What is new is just how long, how steadily, and how much it has declined. University of Washington researchers compiled modern and historic measurements to ...

Sun cycles should be approximately the same from every 11th year, not 0.165c hotter every 11th year relative to the previous 11th year.

After all, the U.S. is breaking record all time highs, and daily highs by 5F to 10F all over the place, especially the appalachians, and the trend continues. This is like 5C above the previous record day time high in a 120 year record...nope, sun cycles don't explain that at all...certainly not 11 year cycles anyway...

You realize we have satellites doing complete orbits of the sun, recording all sun spots on all sides.

Hundreds of years ago, or even just a few decades ago, they did not have this. In fact, they had relatively crappy tools for viewing the Sun which would have made getting an accurate count night to impossible.

"seems to be accelerating" is not objective enough for me. It seems that the globe is cooling, it's July 4th in SoCal and the temperature was in the 60's today.

We're talking about a complex global system with changes in climates across the world - whether it's more abnormal weather, warmer temperatures, colder temperatures, more or less rain, more disasters, etc. It does humor me, by the way, that you seek objectiveness, then state 'But this year it's cooler where I am than I remember it being in previous years.'

You realize we have satellites doing complete orbits of the sun, recording all sun spots on all sides.

Hundreds of years ago, or even just a few decades ago, they did not have this. In fact, they had relatively crappy tools for viewing the Sun which would have made getting an accurate count night to impossible.

"it seems likely that over the last 500 years the sun has played a role in the changing climate. However, there is little evidence to suggest that changes in irradiance are having a large impact on the current warming trend. "http://ppg.sagepu...abstractThe sun WAS a factor in the past, BUT not now?